Sales processing apparatus with early failure detection and method for early failure detection in a sales processing apparatus

2. The point-of-sale terminal according to claim 1, wherein the first reference time is calculated using a plurality of previously acquired times required for the optical scanner to read a code symbol in a plurality of different sales transactions.

3. The point-of-sale terminal according to claim 1, wherein the second reference time is calculated using a plurality of previously acquired times required for the currency handling device to dispense a bill as change in a plurality of different sales transactions.

4. The point-of-sale terminal according to claim 1, wherein the third reference time is calculated using a plurality of previously acquired times required for the coin handling device to dispense a coin as change in a plurality of different sales transactions.

5. The point-of-sale terminal according to claim 1, the first reference time is a first fixed value, the second reference time is a second fixed value, and the third reference time is a third fixed value.

6. The point-of-sale terminal according to claim 1, wherein the optical scanner is a hand-held type scanner.